Fifty Plus (50+) - Question about Trek 'Virtual / Actual' sizing.

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oldbikeguy
03-23-11, 11:58 AM
I’m looking at buying a slightly used 2005 Trek 1000C. Unfortunately I’m not able to see the bike in person. The sizing sticker on the bike says “Virtual 58 / Actual 53”.

Compared to the sizes I’m use to seeing 54, 56, et al; What size is this bike?

Thanks in advance
David


Mr. Beanz
03-23-11, 12:22 PM
I'd say 58 cm.

Most the time virtual mean the direct distance from the seatpost to the headtube on frames with a sloping toptube such as the Pilot and other compact frames.

Most 58 cm bikes have a toptube of 58 cm.

If it's referring to the seatube length, then the shorter distance will be the actual since it is a sloping totube. The vritual will be the ditance to the imaginary tube had it been straight, which would be a greater distance, more like a 58.

I could be wrong but I'm betting a 58cm bike.

Bike was sized in 50-54-58 and 63.......I can't find the geo chart for this model.:(

http://www.trekbikes.com/au/en/bikes/2005/archive/1000c

CACycling
03-23-11, 12:36 PM
I'd say Beanz is right. I looked at a pic of the bike on bikepedia and the top tube is sloped quite a bit.


Mr. Beanz
03-23-11, 01:09 PM
Gina's Pilot size 47 (similar slope on tube)

The virtual is 47 (the longer dimension) and the actual is 46 (shorter dimension).

With the difference in size frame dimensions you posted, may change the ratio of the difference in dimensions. As well as maybe a slightly different geometry.

But usually the virtual is the actual distance ina straight line. 58 cm bikes usually havea 58 top tube length.

As her 47 has a 47 virtual toptube length.


http://img854.imageshack.us/img854/859/img5997a.jpg

stapfam
03-23-11, 04:31 PM
http://img854.imageshack.us/img854/859/img5997a.jpg

All the frames I have known and the measurement given for frame size is the length of the seat tube. So the Actual size of 53 would be that the frame is a compact frame and that is the height of the join of the seat tube to the top tube (Or possibly where the Seat clamp is)----And the size of 58 would be the height of the seat tube with a line drawn as if the frame had a level top tube as measured on a conventional frame

So the frame if built as a conventional frame would be a 58 with the Top tube of the length to suit that size of frame. But if you are looking at it as a 53-- then it may fit on saddle height but the Reach to the bars may be a bit long and the bars may be a bit higher than you are wanting.

Mr. Beanz
03-23-11, 04:50 PM
That's right, I put the virual in as a point to show that the 47 toptube length corresponds to the 47 size of the bike which is the seat tube.

I shouldn't have put in the 46 in this case which was only to show the difference between virtual an actual. I only made it confusing, I confused myself.:D

But I still say it's a 58.:thumb:

Mr. Beanz
03-24-11, 09:49 AM
Hmm, strange how people post then vanish without so much as a yeah you're right, no you're not, or a shut up stupid.:D